Drama series contains the joy and sorrows of police officers at a precinct office. They try to uphold values in everyday life and maintain justice. Jung-O [Jung Yu-Mi] lives with her single mother and her father has ignored her existence. After graduating from college, Jung-O struggles to find a job. One day, she decides to take an exam to become a police officer. She studies for 2 years and finally passes the exam. Jung-O enters the police academy. There, she meets fellow cadet Sang-Soo [Lee Kwang-Soo]. Sang-Soo has a mother and an older brother. He worked as an intern at a water company. He wanted to become a full time employee there and worked incredibly hard, even buying stock in the company. Sang-Soo was devastated to learn that the company was a fraud. He saw a notice announcing an exam to become a police officer. He decided then to become a police officer. Jung-O and Sang-Soo go through hard times at the police academy, led by their instructor Yang-Chon [Bae Sung-Woo]. After training at the police academy, Jung-O and Sang-Soo begin work at the Hongil Police Precinct Office. They encounter situations they never expected. Their instructor Yang-Chon receives a demotion and also begins work at the Hongil Police Precinct Office.